I would advise you to invest only in those projects in which you are personally confident. These are often projects from the top 50 cryptocurrencies by capitalization.
Since we are talking about the two great coins, nothing else but Bitcoin and ETH comes into my mind. Despite the fall in the value and despite the down market, I still suggest these two great coins to invest in for long term. We have seen enough drops in the market before as well and this is another drop which will take time to recover but eventually will. Besides, I do not see any other coins more competent and with an advanced project like this one it gives a feeling of safety to stay by your choice.